Credit scores and how they work should be standard knowledge for anyone who wants to stay on top of their financial situation. HowStuffWorks has a good six-part article on how credit scores are calculated, how you can improve your score, what your score affects, etc.
Credit scores are starting to be factored into more and more of life, unfortunately: insurance quotes, even job interviews, so knowing about your credit score is pretty important. If you've got tips on improving your credit score - legit tips - please share them in the comments.